Flexible boot with active electrode monitoring shield for flexible-wristed surgical devices

ABSTRACT

A boot for an electrosurgical instrument has a conductive boot shield substantially enclosed by one or more insulating layers. The boot shield has a flexible conductive medium. The flexible conductive medium has a plurality of conductive components suspended in at least one of a first liquid or a first gel, whereby the boot is configured to bend with a bend radius of about 10 millimeters or less without a loss in conductivity of the boot shield. A related method and system are also provided.

PRIORITY AND RELATED APPLICATIONS

This application is a utility conversion of, and claims the benefit of,U.S. Provisional Application No. 62/335,447, filed on May 12, 2016,entitled “FLEXIBLE BOOT WITH ACTIVE ELECTRODE MONITORING SHIELD FORFLEXIBLE-WRISTED SURGICAL DEVICES”, the entire disclosures of which areincorporated by reference for all proper purposes.

FIELD

The invention relates to electrosurgical procedures, techniques, anddevices that utilize enhanced control systems such as robotics and othermotion control apparatuses.

BACKGROUND

Electrosurgical systems for minimally invasive surgical proceduresutilizing a flexible or articulating wristed device are common inrobotic surgical systems or other enhanced control systems. In suchsystems, a challenge of the design for monopolar instruments is that theelements of the flexing or articulating wrist or other elements of theinstrument are at active potential, introducing a risk of unintendedpatient burns. There remains a need for a device or method that reducesthe risk of patient burns, and/or other new and innovative features.

SUMMARY

An exemplary boot for an electrosurgical instrument has a conductiveboot shield substantially enclosed by one or more insulating layers. Theboot shield has a flexible conductive medium. The flexible conductivemedium has a plurality of conductive components suspended in at leastone of a first liquid or a first gel, whereby the boot is configured tobend with a bend radius of about 10 millimeters or less without a lossin conductivity of the boot shield.

An exemplary method of retrofitting an electrosurgical instrumentincludes providing a boot. The boot has a conductive boot shieldsubstantially enclosed by one or more insulating layers. The boot shieldhas a flexible conductive medium. The flexible conductive medium has aplurality of conductive components suspended therein. The boot isconfigured to bend with a bend radius of about 10 millimeters or lesswithout a loss in conductivity of the boot shield. The exemplary methodfurther includes placing the boot on an electrosurgical instrument,wherein the placing includes placing the boot over a portion of a shaftof the instrument and a portion of an active element of the instrument.The exemplary method further includes electrically coupling the bootshield to a monitor system. The exemplary method further includesbending the active element relative to the shaft without causing theboot shield to lose conductivity.

An exemplary boot assembly for an electrosurgical instrument includes aboot having a boot shield. A first conductive element is coupled to theboot shield and extends exterior of the one or more insulating layers.The first conductive element may electrically couple the boot shield toa monitor system. The boot shield and a distal portion of the firstconductive element are rotatable with a rotating shaft of theelectrosurgical instrument relative to a non-rotating portion of theelectrosurgical instrument.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an exemplary boot positioned on asurgical tool;

FIG. 2 illustrates a cross section of details of an exemplary bootshield suitable for use in the boot in FIG. 1;

FIG. 2A illustrates a cross section of details of an exemplary bootshield suitable for use in the boot in FIG. 1;

FIG. 3A illustrates an exemplary boot shield suitable for use in theboot in FIG. 1;

FIG. 3B illustrates an exemplary boot shield suitable for use in theboot in FIG. 1;

FIG. 3C illustrates an exemplary boot shield suitable for use in theboot in FIG. 1;

FIG. 4 illustrates a cross section of details of a boot shield suitablefor use in the boot in FIG. 1,

FIG. 5 is a perspective view of an exemplary tool in use with the bootin FIG. 1;

FIG. 6 is a cross section of details of an exemplary boot shield in theboot in FIG. 1;

FIG. 7 is a perspective view of an exemplary tool suitable for use withthe boot in FIG. 1;

FIG. 8A is a side view of an exemplary connector assembly suitable foruse with the tool in FIG. 7 and the boot in FIG. 1; and

FIG. 8B is a side section view of an exemplary connector assemblysuitable for use with the tool in FIG. 7 and the boot in FIG. 1; and

FIG. 9 is a flowchart of an exemplary method.

DETAILED DESCRIPTION

As previously described, there remains a need for a device or methodthat reduces the risk of patient burns, and/or other new and innovativefeatures. With reference now to FIG. 1, in some embodiments describedherein, Applicants provide an insulating boot 100 shaped to bepositioned about a linkage in an electrosurgical tool. For example, thetool may have an electrosurgical active element 210 coupled to aninstrument shaft 220 by way of an active wrist or other linkage (notshown). The wrist may be configured to enable bending of the activeelement 210 relative to the shaft 220. The shaft 220 may be configuredto rotate the active element 210 relative to a support (not shown) ormonitor (not shown). For the purpose of this document, the term “distal”shall be associated with that region of a component approaching orclosest to an active element 210, and the term “proximal” shall beassociated with that end of a component approaching or closer to aposition of a user, support, or robotic control device.

Applicants disclose a boot in co-pending U.S. application Ser. No.15/070,828, filed on Mar. 15, 2016, and titled “ENHANCED CONTROL SYSTEMSINCLUDING FLEXIBLE SHIELDING AND SUPPORT SYSTEMS FOR ELECTROSURGICALAPPLICATIONS,” the entire contents of which are incorporated herein byreference for all proper purposes.

In some embodiments, the boot 100 may include or be coupled to aconductive element 110 to drain energy from the boot 100 to aninstrument cable and/or Active Electrode Monitoring monitor (not shown).The conductive element 110 may extend at least a portion of the lengthof the instrument shaft 220, but those skilled in the art will recognizethis is not a requirement.

In some embodiments, the boot 100 is disposable.

The boot 100 may be flexible, to allow movement of the instrument wristand the active element 210. The boot 100 may comprise an elastomericmaterial 120, such as silicone or thermoplastic elastomer (TPE). Theboot 100 may have a distal end 112 and a proximal end 114, and alongitudinal axis A extending therebetween.

For example, an elastomeric layer may be formed as a boot 100 that maybe a stretch fit over the wrist portion of the instrument 200. A lowdurometer elastomer may be provided to fill in contours of the wristmechanism. Some embodiments (see e.g. FIG. 2) include a compositeconstruction with a very low durometer elastomer as a first insulatinglayer 122 and a higher durometer, tougher skin as a second insulatinglayer 126 to provide resistance to abrasion or cuts. Air spaces can befurther reduced by adding a biocompatible medical grade conductivelubricant or gel to the inside of the boot 100.

With air spaces minimized corona heating will be minimized through theuse of a low dielectric constant inner insulation such as PTFE in athickness of between about 0.05 millimeters and 0.15 millimeters. Theboot 100 may be configured to operate with a power source (not shown)controlled to have an operating frequency of less than 500 KHz, a peakvoltage of less than 3.0 KV, a maximum activation time of 10 seconds,and a duty cycle of less than 30%. With these insulating and drivingparameters, a maximum external temperature rise of less than 3 degreescentigrade is achievable.

As illustrated in FIG. 2, in some embodiments, the boot 100 may includethree or more layers. For example, the boot 100 may have a firstinsulating layer 122, a second insulating layer 126 positioned exteriorof the first insulating layer 122, and a conductive boot shield 124 atleast partially positioned therebetween or substantially enclosed by thelayers 122, 126. The first insulating layer 122 may be shaped andpositioned to separate the boot shield 124 from active current (notshown) traveling through the electrosurgical instrument 200. The firstinsulating layer 122 should be sufficiently thick to prevent coronaheating. In some embodiments, the first insulating layer 122 is at least0.127 millimeters thick, or more, depending on the properties of thematerial used and high-frequency potentials applied. The secondinsulating layer 126 may be shaped and positioned to separate the bootshield 124 from tissue, and to prevent arcing from the active element210 to the boot shield 124. Specifically, those skilled in the art willrecognize that, without a boot 100, energy may tend to pass throughtissue adjacent the active element 210 and around the instrument toother elements in the instrument 200. Similarly, energy may tend to passfrom the active element 210 through air gaps between the instrument 200and tissue to other conductive elements in the instrument 200. The boot100 may insulate conductive elements in the instrument 200 from thisunintentional energy transfer.

The first and second layers 122, 126 may be unitary, such as folded orformed about the boot shield 124.

The boot shield 124, positioned between the first and second layers, maybe conductive, and may include conductive wires, embedded components,and/or other conductive media. The boot shield 124 may be connected tothe conductive element 110, which may include conductive shield wire(s)along the shaft 220.

Some embodiments of the boot shield 124 may include a layer of aflexible conductive medium deposited on a substrate. The substrate mayinclude an elastomeric material, a polymeric material, and/or a flexiblefabric 129 (see e.g. FIG. 2A). The medium may be impregnated into orpositioned on the substrate, and/or positioned on one or both of theinsulating layers 122, 126. The conductive medium may be deposited onthe substrate by way of sputter coating, vapor deposition and/or othermethods. In some embodiments, the conductive element 110 may be coupledto the conductive medium 128 to form an assembly, and then the assemblymay be dip coated to form the second insulating layer 126. In someembodiments, a second elastomeric tube or molding may be slipped overthe assembly and bonded at proximal and distal ends of the conductivemedium 128 to seal the conductive medium 128 from tissue and activecurrent.

A particular challenge is maintaining conductivity and coverage of theboot shield 124 during flexure of the boot 100. The flexing of the boot100 may tend to break the material of the conductive medium 128 due tohigh stress within the conductive medium 128. Moreover, flexing amaterial with embedded components may modify conductivity of the bootshield 124.

To counter this tendency, the boot shield 124 may be a layer aconductive medium 128 that is not uniform throughout the layer betweenthe first and second insulating layers 122, 126. That is, the conductivemedium 128 may be a coating deposited on one or both layers 122, 126 ina pattern, such as a grid, in which the conductive medium 128 isrelatively small compared to the thickness of the insulating layers.

In some embodiments, the boot shield 124 may include or be a conductivelayer having an elastomeric material embedded with conductivecomponents, such as carbon, silver, and/or other conductive material.The boot shield 124 may be sandwiched between the two insulating layers122, 126, as described above, or dip coated or over-molded to createinsulation all around the boot shield 124.

In some embodiments, the boot shield 124 may include a conductive medium128 having a thin wire mesh or matrix. In some embodiments, the wire maybe braided, or coiled around a distal portion of the boot 100, like aspring. This wire may be bonded to the conductive element 110.

With brief reference to FIG. 2A, in some embodiments, the boot shield124 may include a conductive medium 128 such as a conductive liquidand/or conductive gel formed on or about or soaked into or depositedonto a substrate; the substrate may be a thin flexible fabric 129. Aconductive medium made in this fashion may prevent the liquid and/or gelfrom being squeezed out of regions between the first and secondinsulating layers 122, 126.

In some embodiments, the boot shield 124 may include a conductive layerhaving a liquid or gel medium, such as a conductive liquid or conductivecomponents suspended in a non-conductive medium such as a gel (notshown). In some embodiments, the boot shield 124 may include two liquidsthat are immiscible, with one of the liquids being conductive. In someembodiments, a liquid and a gel may be provided, with one of the liquidor gel being conductive. In some embodiments, two or more gels may beprovided, with at least one gel being substantially non-conductive.

In some embodiments, a conductive medium, liquid or gel, is formed bycreating a suspension of conductive nanoparticles in a low durometerpolymer medium or polymer gel. The conductive nanoparticles may be, forexample, silver particles on the order of 20 to 50 nm; however, otherconductive materials are contemplated herein. That is, the boot shield124 may include a flexible conductive medium having a first liquid 134and/or a first gel 134, and a plurality of conductive components 136suspended therein (see e.g. FIG. 3C). The plurality of conductivecomponents 136 may be a plurality of conductive particles, a liquid thatis immiscible with the first liquid and/or first gel 134, and/or aplurality of gel components that are suspended in the first liquidand/or the first gel 134. Although FIG. 3C illustrates the flexiblemedium with a liquid or gel 134 and conductive components 136 with anarray 130 (to be discussed in more detail below), the array 130 is notpresent in all embodiments having the liquid/gel 134. Specifically, insome embodiments, the liquid/gel 134 and conductive components 136 mayalso be impregnated into and/or deposited on a flexible substrate, suchas an elastomeric material, a polymeric material, and/or a fabric, suchas the substrate or fabric 129 illustrated in FIG. 2A. This may beachieved with a nanoparticle suspension in ink and printed in an arrayonto the substrate. Further, multiple patterns with varying viscositiesor durometers may be applied to achieve the desired conductivity andcoverage.

In some embodiments, the boot shield 124 may include a flex circuit 138or similar wire arrangement, and/or may be formed in a single piece withthe conductive element 110. The distal portion of the flex circuit 138may be an array 138 of conductors that allows sufficient coverage forshielding, but is thin enough to allow flexure of the instrument wrist.The array 138 of conductors may be configured as fingers, featherpatterns, or bellows. The array 138 may be deposited such as by way of aspray deposition on one or more of the layers 122, 126.

With reference to FIG. 3C, in some embodiments, the boot shield 124 mayhave a flexible wire arrangement 130 or array of conductors, with aconductive suspension 132 deposited in gaps between the portions of thewire arrangement 130. The suspension 132 may include a liquid or gel 134having a plurality of conductive components 136 suspended therein. Thecombination of a conductive wire arrangement 130 and less conductivesuspension 132 may create a preferential conductive pathway, wherebystray energy will couple to the boot shield 124 and not to the patient.

In some embodiments, the conductive element 110 may be a straight flatribbon, which may be coupled to the shaft 220 using an adhesive strip(not shown) or any suitable coupling mechanism.

If the boot shield 124 has a wire arrangement 130, the maximum spacing Dbetween wire conductors may be about 0.5 millimeters if no conductivesuspension 132 is provided. However, if the wire arrangement 130 is incombination with a conductive suspension 132, the spacing D may begreater. In some embodiments, the spacing D is 0.55 millimeters or more.In some embodiments, the spacing D is 1 millimeter or more. In someembodiments, the spacing is 1.5 millimeters or more. In someembodiments, the spacing is 2.0 millimeters or more. In someembodiments, the spacing is 3 millimeters or less. By providing a bootshield 124 with a wire arrangement 130 and a conductive suspension 132,Applicants provide a method in which flexibility of the boot shield 124is maximized without sacrificing the protective nature (conductivity) ofthe boot shield 124 or risking fracturing regions of conductivity in theboot shield 124.

The array of thin conductors 130, 138 allows the stresses induced in theconductors 130, 138 by flexing to be sufficiently low that splitting ofeach conductor is prevented and conductivity is maintained. Turningagain to FIGS. 3A-3B, an array example is 0.05 mm conductor width W andseparation having 50% coverage. The conductor array 138 may besandwiched between two insulating layers 122, 126 (see e.g. FIG. 2), andeach insulating layer 122, 126 may be about 0.15 mm thick. In someembodiments, the boot 100 is configured to bend on a radius of about 10millimeters or less while maintaining full conductivity. In someembodiments, the boot 100 is configured to bend on a radius of about 5millimeters or less while maintaining full conductivity.

With reference now to FIG. 4, one particular challenge is maintainingelectrical separation of the boot shield 124 from the active element210. Any break in insulation (e.g. insulating layer 122) between theboot shield 124 and active current would result in shutdown of thesystem, as the energy would preferentially transfer to the boot shield124.

To solve this problem, and as previously alluded herein, one method ofproduction may include positioning the boot shield 124 between twoinsulating layers 122, 126 and then sealing at least one of the ends 140of the insulating layers 122, 126 at sealing 142. The end(s) 140 may besealed using heat, lasers, chemical bonding or adhesive or any othermethod typically used in the industry.

In some embodiments, and with continued reference to FIG. 4, the firstand second insulating layers 122, 126 may be formed of a single tubularmaterial, folded about the boot shield 124 at a first end 144 and sealedat a second end 140 to isolate the boot shield 124 from tissue and theactive element 210.

FIG. 5 illustrates the conductive element 110 coupled to the boot shield124 and wound about the shaft 220, thereby providing excess length forrotation of the shaft 220 relative to a support (not shown).

Turning now to FIG. 6, some embodiments described herein may beconfigured to minimize or eliminate distance (air) 650 between the boot630 and the active element 210 of the instrument wrist. For example, theboot 630 may include an outer insulating layer 640 that is unitary withor coupled to an insulating layer 620 that is coupled or adjacent to theshaft 600 of the instrument. A conductive layer 610 may extend betweeninsulating portions 620, 640, of the boot 630.

Some embodiments of the conductive layer 610 may include a thinconductive tube. This layer 610 or tube may provide additional benefitof shielding the instrument shaft as well. The layer 610 or thinconductive tube may not necessarily require an inner insulating layer,as the shaft of the instrument may be insulated as well.

With reference now to FIGS. 8A-8B, a particular challenge is that ofelectrically connecting a sheath or boot 100 on a rotating shaft to astationary housing. Examples are the Intuitive Surgical Si or Xiinstruments, which have a shaft that rotates approximately 540 degrees,but other instruments could rotate 360 to 720 degrees or even have nolimitation on rotation. Some embodiments of the invention could includea helical coil at the proximal end, near the instrument housing, thatwould allow rotation of the shaft, up to 720 degrees. This could beadapted to either a printed flex circuit configuration, where the flexcircuit is adhered to the side of the shaft or a simple wire connectedto a sheath extending the full length of the shaft.

With reference now to FIG. 7, in conjunction with FIGS. 8A-8B, in someembodiments, a boot 100 (see e.g. FIG. 1) may be provided for use withan electrosurgical instrument having a distal end with an active element210 that is movably or bendably attached to a shaft 220. The shaft 220may be coupled to or include a housing or shaft connection assembly 710.The shaft connection assembly 710 may include a cable connector 720 forelectrically coupling the active element 210 (see e.g. FIG. 1) to acontrol unit or monitor (not shown). The boot 100, not illustrated inFIG. 7, may be positioned about the linkage 730 between the activeelement 210 and the shaft 220, and the conductive element 110 may extendtowards the connection assembly 710, for coupling to the control ormonitor.

As illustrated in FIG. 8A, a proximal structure may include a monitorconnector 803 shaped and configured to engage the cable connector 720associated with the shaft in FIG. 7 to the conductive element 110. Theconductive element 110 may include a distal portion 801 and a proximalportion 802. The proximal portion 802 may be wound about the shaft 220so as to enable the shaft 220 to rotate relative to stationary portionsof the device for the housing 710. The distal portion 801 may beattached to the shaft 220. The boot 100 may be electrically coupled tothe monitor (not shown) by way of conductive element 110 (see FIG. 1).The connectors 803, 720 may couple the conductive element 110 to themonitor. In some embodiments, the instrument 200 is rotated relative tothe housing 710. In some embodiments, the instrument 200 is rotatedrelative to the monitor, robotics, or other controls and supportsystems. In some embodiments, the instrument 200 and housing 710 arefixed relative to each other.

In some embodiments, the proximal portion 802 may be wound about theshaft 220 a selected number of times to minimize a change in diameter dof a coiled portion of the conductive element 110 while still allowingenough slack for tightening. The conductive element 110 may beconfigured to allow up to 720 degrees of rotation of the shaft 220relative to stationary portions, such as the housing 710.

In some embodiments, a loose sleeve (not shown) or other housing may beprovided about the proximal portion 802 to prevent the coils fromtangling with or contacting other objects.

With reference now to FIG. 8B, in some embodiments, the shaft 220 mayinclude a brush contact with stationary or non-rotating componentfeatures, such as the instrument housing 710. The housing 710 mayinclude one or more brush contacts 806 or a slip ring that electricallyconnects with the shield or conductive element 110, 804. In thisembodiment, instrument arms with unlimited rotation may be provided. Theshaft 220 may include an insulating layer 805 surrounding the conductiveelement 804. A housing 809 may insulate the contacts 806 from othercomponents, and a connector 807 may couple the contacts 806 to thehousing 710 and/or the conductive element 110, such as by way ofconnector 803.

The active element 210 may be shaped and configured to rotate up to 540degrees about a longitudinal axis relative to the housing 710 and/orother non-rotating portions of the system. In some embodiments, theactive element 210 may be shaped and configured to rotate up to 720degrees about the longitudinal axis relative to the housing 710 and/orother non-rotating portions of the system.

With any embodiment, a connection of the shield must be made to theinstrument cable. Any embodiment of the invention may include aconnector that adapts to the instrument cable connector. One method tomake the connections is a cable connector attached to the shield by aconductor and the cable connector plug in or on the instrument activeconnector. In some embodiments, the connector is an AEM connector thatslips over the banana plug connector of an Intuitive Surgical Siinstrument. An AEM cord may then be attached to the connector with theshield and active current input(s). Other instrument types may havedifferent types of connectors, but a similar method may be employed, orvarious adapters could be manufactured to work with a common shieldconnector.

Some embodiments of the conducting shield element along the instrumentshaft may include the ribbon flex circuit described above. Although itis described above as integrated with a distal flex circuit pattern, theshield element may be combined with any of the above embodiments, forexample, connected to another flexible conductive medium.

Some embodiments of the conducting shield element include either a flatribbon or round wire embedded in a tubular sheath. Utilization of asheath may eliminate the need to adhere the conductor to the shaft.

Any of the embodiments could be configured as either a sheath thatextends the full length of the shaft, a boot that only covers the distalportion of the shaft and instrument wrist, or a combination of the two.The invention could work with an existing non-shielded boot or it couldincorporate a boot, replacing the need to install a separate boot.

The use of a conductive element such as the conductive element 110previously described herein may assist in retaining the boot 100 and maymitigate the risk of the boot 100 falling off into the patient. In someembodiments, a method of retaining a boot by way of a return electrodeor conductive element may be provided.

The terms and expressions employed herein are used as terms andexpressions of description and not of limitation, and there is nointention, in the use of such terms and expressions, of excluding anyequivalents of the features shown and described or portions thereof. Inaddition, having described certain embodiments, it will be apparent tothose of ordinary skill in the art that other embodiments incorporatingthe concepts disclosed herein may be used without departing from thespirit and scope of the disclosure. Accordingly, the describedembodiments are to be considered in all respects as only illustrativeand not restrictive.

With reference now to FIG. 9, a method 900 of retrofitting anelectrosurgical instrument includes providing 902 a boot. The boot has aconductive boot shield substantially enclosed by one or more insulatinglayers. The boot shield has a flexible conductive medium. The flexibleconductive medium has a plurality of conductive components suspendedtherein. The boot is configured to bend with a bend radius of about 10millimeters or less without a loss in conductivity of the boot shield.The method 900 further includes placing 904 the boot on anelectrosurgical instrument, wherein the placing 904 includes placing theboot over a portion of a shaft of the instrument and a portion of anactive element of the instrument. The method 900 may further includeelectrically coupling 906 the boot shield to a monitor system. Themethod 900 may further include bending 908 the active element relativeto the shaft without causing the boot shield to lose conductivity. Themethod 900 may be achieved using the boot 100 previously describedherein.

Each of the various elements disclosed herein may be achieved in avariety of manners. This disclosure should be understood to encompasseach such variation, be it a variation of an embodiment of any apparatusembodiment, a method or process embodiment, or even merely a variationof any element of these. Particularly, it should be understood that thewords for each element may be expressed by equivalent apparatus terms ormethod terms—even if only the function or result is the same. Suchequivalent, broader, or even more generic terms should be considered tobe encompassed in the description of each element or action. Such termscan be substituted where desired to make explicit the implicitly broadcoverage to which this disclosure is entitled.

As but one example, it should be understood that all action may beexpressed as a means for taking that action or as an element whichcauses that action. Similarly, each physical element disclosed should beunderstood to encompass a disclosure of the action which that physicalelement facilitates. Regarding this last aspect, by way of example only,the disclosure of an active element should be understood to encompassdisclosure of the act of activating the element—whether explicitlydiscussed or not—and, conversely, were there only disclosure of the actof rotating, such a disclosure should be understood to encompassdisclosure of a rotating mechanism. Such changes and alternative termsare to be understood to be explicitly included in the description.

The previous description of the disclosed embodiments and examples isprovided to enable any person skilled in the art to make or use thepresent disclosure as defined by the claims. Thus, the presentdisclosure is not intended to be limited to the examples disclosedherein. Various modifications to these embodiments will be readilyapparent to those skilled in the art, and the generic principles definedherein may be applied to other embodiments without departing from thespirit or scope of the invention as claimed.

What is claimed is:
 1. A boot for an electrosurgical instrument,comprising: a conductive boot shield substantially enclosed by one ormore insulating layers; wherein the boot shield comprises a flexibleconductive medium, the flexible conductive medium having a plurality ofconductive components suspended in at least one of a first liquid or afirst gel, wherein the flexible conductive medium comprises the firstliquid and the plurality of conductive components comprises a secondliquid that is immiscible with the first liquid, and whereby the boot isconfigured to bend with a bend radius of about 10 millimeters or lesswithout a loss in conductivity of the boot shield.
 2. The boot of claim1, wherein: the boot is configured to bend with a bend radius of about 5millimeters or less without a loss in conductivity of the boot shield.3. The boot of claim 1, further comprising: a first conductive elementelectrically coupled to the boot shield, the first conductive elementconfigured to electrically couple the boot shield to a monitor system.4. The boot of claim 1, wherein: the flexible conductive mediumcomprises a flexible substrate, and the at least one of the first liquidor the first gel is at least one of impregnated into or deposited on thesubstrate.
 5. The boot of claim 1, wherein: the plurality of conductivecomponents further comprise a plurality of gel components or a pluralityof conductive particles suspended in the first liquid; or the flexibleconductive medium further comprises the first gel and the plurality ofconductive components further comprise a second gel or a plurality ofconductive particles suspended in the first gel, or a combinationthereof.
 6. The boot of claim 1, wherein: the plurality of conductivecomponents further comprise a plurality of gel components suspended inthe first liquid; or the flexible conductive medium further comprisesthe first gel and the plurality of conductive components furthercomprise a second gel suspended in the first gel, or a combinationthereof.
 7. A boot assembly for an electrosurgical instrument,comprising: a boot for an electrosurgical instrument, the bootcomprising a conductive boot shield substantially enclosed by one ormore insulating layers, wherein the boot shield comprises a flexibleconductive medium, the flexible conductive medium having a plurality ofconductive components suspended in at least one of a first liquid or afirst gel, wherein the flexible conductive medium comprises the firstliquid and the plurality of conductive components comprises a secondliquid that is immiscible with the first liquid, and whereby the boot isconfigured to bend with a bend radius of about 10 millimeters or lesswithout a loss in conductivity of the boot shield; a first conductiveelement coupled to the boot shield and extending exterior of the one ormore insulating layers, the first conductive element configured toelectrically couple the boot shield to a monitor system; wherein theboot shield and a distal portion of the first conductive element arerotatable with a rotating shaft of the electrosurgical instrumentrelative to a non-rotating portion of the electrosurgical instrument. 8.The boot assembly of claim 7, wherein: the plurality of conductivecomponents further comprise a plurality of gel components or a pluralityof conductive particles suspended in the first liquid; or the flexibleconductive medium further comprises the first gel and the plurality ofconductive components further comprise a second gel or a plurality ofconductive particles suspended in the first gel, or a combinationthereof.
 9. The boot assembly of claim 7, wherein: the flexibleconductive medium comprises a flexible substrate, and the at least oneof the first liquid or the first gel is at least one of impregnated intoor deposited on the substrate.
 10. A boot for an electrosurgicalinstrument, the boot comprising: a first insulating layer; a secondinsulating layer positioned exterior of the first insulating layer; aconductive boot shield at least partially positioned therebetween orsubstantially enclosed by one or more insulating layers, including atleast the first and second insulating layer, wherein the firstinsulating layer is at least 0.127 millimeters thick and is shaped andpositioned to separate the conductive boot shield from active currenttraveling through the electrosurgical instrument, and wherein the secondinsulating layer is shaped and positioned to separate the conductiveboot shield from tissue; wherein the boot shield comprises a flexibleconductive medium, the flexible conductive medium having a plurality ofconductive components suspended in at least one of a first liquid or afirst gel, wherein the flexible conductive medium comprises the firstliquid and the plurality of conductive components comprises a secondliquid that is immiscible with the first liquid, and whereby the boot isconfigured to limit an external temperature rise due to corona heatingto 3 degrees centigrade or less, and whereby the boot is furtherconfigured to bend with a bend radius of about 10 millimeters or lesswithout a loss in conductivity of the boot shield.